The present invention is related to milk pasteurization and storage, in particular a heat treatment method in which milk is pasteurized and cooled within minutes of being obtained from the animal to increase its shelf life.
Milk is usually stored by the producer in cooled tanks shortly after being obtained from the animals. Cooling the milk helps to inhibit the growth of microorganisms. After a sufficient quantity of milk is contained within the tank, the milk is taken from the producer to the dairy. After the milk arrives at the dairy or like plant, it is heated to kill most microorganisms during pasteurization. After pasteurization it is again cooled. Therefore in the usual case the milk is heated only after it reaches the dairy during pasteurization.
However, this storage in tanks, which is becoming more and more common and the purpose of which is to rationalize and minimize the number of collecting turns, involves the drawback that milk will be kept for a comparatively long time before being subjected to the heat treatment. Though the storage tanks are cooled growth of bacteria can arise; this cannot be accepted either from a hygienic point of view or in view of the quality of the milk or products prepared from the milk. It may be mentioned in this connection that even a very small volume of bacteria-affected goat milk mixed into a larger volume can render the entire milk volume unusable for manufacture of cheese.